"The overriding challenge for our generation is to build a new economy–one that is powered largely by renewable sources of energy, that has a much more diversified transport system, and that reuses and recycles everything." –Lester R. Brown, Plan B 3.0: Mobilizing to Save Civilization

Chapter 3. Climate Change and the Energy Transition: Introduction

Ever since civilization began, each generation has left the next a planet similar to the one it inherited. Our generation may be the first to abandon that tradition.

The earth’s temperature is rising. It has gone up 0.6 degrees Celsius (1 degree Fahrenheit) since 1970, and it is projected to rise by up to 6 degrees Celsius (11 degrees Fahrenheit) by the end of this century. This rise will be uneven. It will be much greater at the higher latitudes than in the equatorial regions, greater over land than over oceans, and greater in continental interiors than in coastal regions. 1

Sea level is rising too, as a result of the thermal expansion that takes place as ocean water warms and as ice sheets melt. Recent studies project a rise of 3–6 feet by the end of the century. During the entire twentieth century, sea level rose by 7 inches, but if it rises 6 feet by 2100, it will have risen an average of 7 inches per decade. 2

Geographically, the oceans will expand and the continents will shrink. Low-lying island countries will disappear beneath the waves. Rising seas will inundate low-lying cities and rice-growing river deltas, generating hundreds of millions of refugees.

The rapidly rising temperature that is projected for this century with business as usual will alter every ecosystem on earth. Up to one third of all plant and animal species could be lost. Despite the fences we have built around parks and wildlife preserves, the ecosystems within them will not survive the thermal stress. 3

Agriculture as we know it today evolved in a climate that was remarkably stable during its 11,000-year experience. As climate changes, agriculture will be increasingly out of sync with it.

At the same time that rising temperatures are reshaping the earth’s ecology and geography, declining oil production will be reshaping the global economy. The twentieth century was the oil century. In 1900, the world produced 150 million barrels of oil. In 2000, it produced 28 billion barrels—a 185-fold jump. This was the century in which oil overtook coal to become the world’s leading source of energy. It was also the century in which oil totally reshaped life for much of humanity. 4

The rapidly expanding supply of cheap oil led to an explosive worldwide growth in food production, population, urbanization, and human mobility. But today’s oil-based civilization is heavily dependent on a resource whose production will soon be falling. Since 1981, oil extraction has exceeded new discoveries by an ever-widening margin. In 2008, the world pumped nearly 31 billion barrels of oil but discovered only 7 billion barrels. World oil reserves are now in decline, dropping every year. 5

As we look at the future of oil in a Plan B context, it is not only geological constraints but also escalating climate concerns that will reduce its use. Today roughly 43 percent of carbon dioxide (CO2) emissions from burning fossil fuels comes from coal and 38 percent from oil. The remaining 19 percent comes from natural gas. Because coal is the most carbon-intensive fossil fuel, any effort to quickly cut CO2 emissions means quickly cutting coal use. 6